Officials say actress Carrie Fisher died from sleep apnea and a combination of other factors, but they could not conclusively determine what caused her death.

Los Angeles coroner’s officials said in a news release late Friday that Fisher had buildup of fat in the walls of her arteries. The release states that Fisher had taken multiple drugs prior to her death, but that investigators could not determine whether they contributed to her death in December.

The agency did not immediately respond to a request for additional details about whether a full autopsy report and toxicology results were available.

Fisher fell ill on a flight from London to Los Angeles and was rushed to the hospital. Emergency workers who met the plane said she was unresponsive. Several people who were on the flight tweeted that they saw her receive CPR from passengers who may have been nurses. The plane was then met by paramedics at LAX who provided advanced life support.

Her mother, longtime movie star Debbie Reynolds, died the following day.

Fisher’s brother, Todd Fisher, said he was not surprised by the results. He added that his family did not want a coroner’s investigation of his sister’s death. “We’re not enlightened. There’s nothing about this that is enlightening,” he said.

“I would tell you, from my perspective that there’s certainly no news that Carrie did drugs,” Todd Fisher said. He noted that his sister wrote about her drug use frequently, and that many of the drugs she took were prescribed by doctors to try to treat her mental health conditions.

Fisher long battled drug addiction and mental illness. She said she smoked pot at 13, used LSD by 21 and was diagnosed as bipolar at 24. She was treated with electroshock therapy and medication.
“I am not shocked that part of her health was affected by drugs,” Todd Fisher said.

He said his sister’s heart condition was probably worsened by her smoking habit, as well as the medications she took. “If you want to know what killed her, it’s all of it,” he said.

Todd Fisher said it was difficult to blame doctors who treated his sister because they were trying to help her.

“They were doing their best to cure a mental disorder. Can you really blame them?” Todd Fisher said. “Without her drugs, maybe she would have left long ago.”